Humans can evolve even when monogamy limits their potential to produce children, according to research published today (April 30) in Proceedings of the National Academy of Sciences. Using church records of the marriages, births, and deaths of nearly 6,000 people living in Finland in the 18th and 19th centuries, an international team of researchers showed that the population’s reproductive fitness varied enough for natural selection to act.

“This is a good confirming instance, with solid evidence” that humans still have the potential to evolve in modern times, said Stephen Stearns, an evolutionary biologist at Yale University, whose own work has suggested the potential for continuing human evolution beyond prehistoric times. Stearns, who did not participate in the current study, explained that the extremely strong data set, in which researchers could track each individual from birth through death, helped bolster the argument for evolution.

Whether or not humans could continue to evolve after adopting an agrarian, monogamous lifestyle has been hotly debated, said co-author Alexandre Courtiol. Monogamy, for example, limits the numbers of kids people have, and thus reduces the variation in reproductive success among individuals, while agriculture helps buffer people from environmental selection pressures by allowing them to stockpile food. Thus, monogamous, farming humans have a drastically reduced the potential for evolution, Courtiol explained. But some biologists feel that these factors wouldn’t abolish selection pressures altogether, and that humans continue to evolve today.

In order to examine the potential for selective pressures to continue influencing human biology, Courtiol and his collaborators looked at a population of Finns during the period 1760 to 1849. Thorough church records during this time allowed them to track each person from birth, through all marriages, to death, while noting all of their offspring along the way. Because the population was strongly monogamous, explained Stearns, researchers could confidently assign children to specific parents, and thus accurately estimate people’s reproductive success. The more variation in the number of offspring individuals leave to future generations, the more susceptible the population is to selective pressures, such as disease.

Sure enough, Courtiol and his co-authors found that reproductive fitness, or the total number of children each person had, varied enough to allow for selection. The researchers looked at four areas that could contribute to variation— whether the person survived to sexual maturity (age 15), whether he or she married, how many times, and the number of children per marriage—and calculated how much each of these factors influenced overall fitness.

Not surprisingly, the researchers found that the number of children per marriage strongly influenced individual fitness. In addition, they found that survival was an even more important factor, likely because the Finns had a high rate of infant and childhood mortality. Finally, the number of marriages tended to influence men’s fitness, but not women’s. Men who remarried often married a younger woman still capable of bearing children, thereby increasing their own potential number of offspring. Women who remarried, on the other hand, usually did so later in life, after their reproductive window had closed, said Courtiol.

The data suggest that the population may well have been evolving. Traits that benefitted survival, for example, such as resistance to influenza, would have been selected for, and become more common in the population. Courtiol and his collaborators did not measure any specific traits, however, and thus merely demonstrated the potential for selection to occur, not that it did.

And it’s not the first study to find such evidence. Jacob Moorad, an evolutionary biologist at Duke University, and his colleagues published last year a study of 19th century Mormon populations in Utah that suggested the number of marriages strongly influenced male fitness in this polygynous society, while childhood mortality appeared to play a smaller role.

Going forward, combining such data with modern genetic techniques will give a more complete understanding of how humans might evolve over time, said Stearns. “Basically, the take home message is that our fundamental biological nature [may be] changing.”

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It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.â€쳌Charles Darwin

There is no substitute for Trial & Error when dealing with your own well-being.I was introduced to a very interesting train of thought last night on TED. The speaker was Tim Harford.In his presentation, he explains how Unilever designed the perfect nozzle to manufacture laundry detergent. Quite simply in manufacturing detergent you take a liquid form and spray it on a surface to dry. Once dry you package and sell it. The difficulty in the process is getting the nozzle to spray the liquid just right, in the perfect size for drying. Unilever initially hired the most brilliant engineers in the world to design the nozzle and no one could get it right. Eventually they simply began to try hundreds of different designs, and gradually tweak the nozzles that showed promise. Ultimately this approach resulted in the perfect nozzle for manufacturing. No one could explain why it worked so well, it just did.The point is, no expert could design it. Sometimes it doesnâ€™t take the smartest person in the room to get it right. In nature, it is the gradual adaptation through painstakingly slow mutations that result in the most successful results.We are constantly bombarded with the expert opinions, the large corporations telling us exactly what will fix our problems. With health it is generally the largest marketing budget that â€œshouts down from the mountainâ€쳌; we are right, we have the solution.If history can teach us anything; we need to pay attention to works well for us and we do this through the Trial & Error process.Darwin when writing the Origin of Species would have agreed that almost all improvements are a result of Trial & Error. â€œIt is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.â€쳌If you have diabetes, then you need to experiment with a different approach. You need to look for solutions that offer a minute improvement. And then improve on the improvement. If you are overweight you need to examine the cause. Breakdown the data and tweak with the input to get different results.We need to continue to evolve as a species. True change in nature occurs over very long periods of time but we can exploit that knowledge. We can speed up the discovery phase and experiment with our own well-being. Why wait for thousands of years to conclude that the food we are eating is killing us off one by one. The beauty of eating healthy is the change occurs very rapidly. We improve our health and thus improve our lives. We live longer and pass on our habits to the next generation. Albeit these are not genetic changes; yetâ€¦ it does give us the opportunity to change our destiny within our own lifetime.â€œIn a complicated society, we give up to the God-complex, listening to the authorities who have all the answers, instead of facing the task of fixing the problem. Tim Harford tells us that when a problem persists, the method to fix it is simple: trial and error. Experimenting helped me find my perfect running gait. Maybe we can use this method to improve bigger systems, on the scale of societies. Communities can be different and each type needs the leadership and experience of its citizens. If only we can use our humility to admit that we donâ€™t have the answers and our strength to face our problems, fail, and try again. And the confidence to challenge the authorities who tell us they have the answers. By acclimating, we can continue to exist. By reasoning and experimentation, we will thrive.â€쳌 Tim Harfordhttp://www.ted.com/talks/tim_h...

Why would one not expect much human evolution during the past 10,000 years?Â Humans had to adapt to new pathogens associated with agriculture and primitive early urban conditions, had to adapt to new diets provided by agriculture and had to evolve to live productively in early civilizations. The changes from the hunter-gatherer life style were profound. We are still evolving.

Ridiculous. It is impossible to stop evolution. As long as there are selective pressures working on the population - and there are, in the west mainly sexual selection - evolution continues.But paleoanthropology is a joke. I wonder how long it will take before someone realizes that it's odd that modern humans reached Australia 50 000 years ago when they didn't leave africa until 30 000 years ago; or wonders howcome all the geographical races of humans arose in just the short timespan between leaving africa and inventing agriculture but haven't changed since. It's almost as if there's something the paleoanthropologists are missing.

Humans have recently evolved to adapt to very different environments all over the world. Â We've changed skin colors, facial structures, sizes, susceptivity to certain diseases, etc., and (although we don't want to say it) certain types of strategic intelligences. Â All these changes have become consistently heritable where initially they seemed accidental, and are now seen by even the competing modern theorists as evidence of evolutionary changes.

There are two directionsfor evolution, intellectual and spiritual, and one direction for biological involution.

Looking in the Bible,we can easy discover the information about evolution:

Human mind - Daniel 7.2-4 - "Windswere blowing from all directions and lashing the surface of the ocean. Fourhuge beasts came up out of the ocean, each one different from the others. Thefirst one looked like a lion, but had wings like an eagle. While I waswatching, the wings were torn off. The beast was lifted up and made to standlike a man. And then a human mind was given to it."

Human spirit - Paul, 1.Corinthians,15.45-47 - "The first man, Adam, wascreated a living being; but the last Adam is the life-giving spirit. It is not thespiritual that comes first, but the physical, and then the spiritual.The firstAdam, made of earth, came from the earth; the second Adam came from heaven."

In addition for mindevolution:

Proverbs1.22 - "Foolish people! How long doyou want to be foolish? How long will you enjoy pouring scorn on knowledge?Will you never learn?"

Proverbs 25.2 - â€œWehonour God for what He conceals; we honour kings for what they explain!â€쳌

Paul, Romans 12.2 -"Do not conform yourselves to thestandards of this world, but let God transform you inwardly by a completechange of your mind. Then you will be able to know the will of God - what isgood and is pleasing to Him and is perfect."

There is one informationfor the involution too, but not very expressively:

Matthew 23.15 - "How terrible for you, teachers of the lowand pharisees!You hypocrites! You sail the seas and cross whole countries to win one convert;and when you succed, you make him twice as deserving of going to hell asyourselves are."

Â

Based on Adam mtDNA heritage, observed only at the puberty only in"the born boy's" seminalliquid (not in vitro made - missingthe life-giving spirit because paternal mitochondria is eliminated) and , Ihave developed a new bio-communication theory, Mitochondrial Adam DNA datatransmission theory - ISBN978-606-92107-1-0, and, I hope I found the scientific explanation about thespirit (Adam mtDNA bio-magnetic field sensor) and the soul (Eve mtDNA bio-magneticfield sensor), connected in xiphoid process as Paul said in Hebrew 4.12 - "The word of God is alive and active, sharper than any double-edgedsword. It cuts all the way through, to where soul and spirit meet, to wherejoints and marrow come together."Â

I agree with the previous commenters that it is highly unlikely that we have stopped evolving. I doubt we even understand all the different factors that contribute to evolution, so how can we even assess evolution other than genetically?I also find the premise that monogamy = established paternity a bit naive, tending towards moralistic or wishful thinking rather than reality. I recall reading studies that indicate that there is more variability in genetic paternity than one might expect from outwardly monogamous relationships. I'm looking forward to the insights that genetic assessment will bring - I think lots of folks will be surprised!

Two questions not answered by the article above (though possibly in the original publication):Â how do they know that the individual reproductive fitness which they so carefully measure is genetically heritable?Â and what evidence supports the presumption that monogamy (which I take it in this context refers to a social institution) guarantees paternity?Â ;-)

Evolution in the most narrow sense is a change in population gene frequencies.Â Human populations have, do and will evolve.Â Send a group into an isolated island and you will find founder effects relatively soon.Â The headline needed a bit more thought.

It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.â€쳌Charles Darwin

There is no substitute for Trial & Error when dealing with your own well-being.I was introduced to a very interesting train of thought last night on TED. The speaker was Tim Harford.In his presentation, he explains how Unilever designed the perfect nozzle to manufacture laundry detergent. Quite simply in manufacturing detergent you take a liquid form and spray it on a surface to dry. Once dry you package and sell it. The difficulty in the process is getting the nozzle to spray the liquid just right, in the perfect size for drying. Unilever initially hired the most brilliant engineers in the world to design the nozzle and no one could get it right. Eventually they simply began to try hundreds of different designs, and gradually tweak the nozzles that showed promise. Ultimately this approach resulted in the perfect nozzle for manufacturing. No one could explain why it worked so well, it just did.The point is, no expert could design it. Sometimes it doesnâ€™t take the smartest person in the room to get it right. In nature, it is the gradual adaptation through painstakingly slow mutations that result in the most successful results.We are constantly bombarded with the expert opinions, the large corporations telling us exactly what will fix our problems. With health it is generally the largest marketing budget that â€œshouts down from the mountainâ€쳌; we are right, we have the solution.If history can teach us anything; we need to pay attention to works well for us and we do this through the Trial & Error process.Darwin when writing the Origin of Species would have agreed that almost all improvements are a result of Trial & Error. â€œIt is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.â€쳌If you have diabetes, then you need to experiment with a different approach. You need to look for solutions that offer a minute improvement. And then improve on the improvement. If you are overweight you need to examine the cause. Breakdown the data and tweak with the input to get different results.We need to continue to evolve as a species. True change in nature occurs over very long periods of time but we can exploit that knowledge. We can speed up the discovery phase and experiment with our own well-being. Why wait for thousands of years to conclude that the food we are eating is killing us off one by one. The beauty of eating healthy is the change occurs very rapidly. We improve our health and thus improve our lives. We live longer and pass on our habits to the next generation. Albeit these are not genetic changes; yetâ€¦ it does give us the opportunity to change our destiny within our own lifetime.â€œIn a complicated society, we give up to the God-complex, listening to the authorities who have all the answers, instead of facing the task of fixing the problem. Tim Harford tells us that when a problem persists, the method to fix it is simple: trial and error. Experimenting helped me find my perfect running gait. Maybe we can use this method to improve bigger systems, on the scale of societies. Communities can be different and each type needs the leadership and experience of its citizens. If only we can use our humility to admit that we donâ€™t have the answers and our strength to face our problems, fail, and try again. And the confidence to challenge the authorities who tell us they have the answers. By acclimating, we can continue to exist. By reasoning and experimentation, we will thrive.â€쳌 Tim Harfordhttp://www.ted.com/talks/tim_h...

Why would one not expect much human evolution during the past 10,000 years?Â Humans had to adapt to new pathogens associated with agriculture and primitive early urban conditions, had to adapt to new diets provided by agriculture and had to evolve to live productively in early civilizations. The changes from the hunter-gatherer life style were profound. We are still evolving.

Ridiculous. It is impossible to stop evolution. As long as there are selective pressures working on the population - and there are, in the west mainly sexual selection - evolution continues.But paleoanthropology is a joke. I wonder how long it will take before someone realizes that it's odd that modern humans reached Australia 50 000 years ago when they didn't leave africa until 30 000 years ago; or wonders howcome all the geographical races of humans arose in just the short timespan between leaving africa and inventing agriculture but haven't changed since. It's almost as if there's something the paleoanthropologists are missing.

Humans have recently evolved to adapt to very different environments all over the world. Â We've changed skin colors, facial structures, sizes, susceptivity to certain diseases, etc., and (although we don't want to say it) certain types of strategic intelligences. Â All these changes have become consistently heritable where initially they seemed accidental, and are now seen by even the competing modern theorists as evidence of evolutionary changes.

There are two directionsfor evolution, intellectual and spiritual, and one direction for biological involution.

Looking in the Bible,we can easy discover the information about evolution:

Human mind - Daniel 7.2-4 - "Windswere blowing from all directions and lashing the surface of the ocean. Fourhuge beasts came up out of the ocean, each one different from the others. Thefirst one looked like a lion, but had wings like an eagle. While I waswatching, the wings were torn off. The beast was lifted up and made to standlike a man. And then a human mind was given to it."

Human spirit - Paul, 1.Corinthians,15.45-47 - "The first man, Adam, wascreated a living being; but the last Adam is the life-giving spirit. It is not thespiritual that comes first, but the physical, and then the spiritual.The firstAdam, made of earth, came from the earth; the second Adam came from heaven."

In addition for mindevolution:

Proverbs1.22 - "Foolish people! How long doyou want to be foolish? How long will you enjoy pouring scorn on knowledge?Will you never learn?"

Proverbs 25.2 - â€œWehonour God for what He conceals; we honour kings for what they explain!â€쳌

Paul, Romans 12.2 -"Do not conform yourselves to thestandards of this world, but let God transform you inwardly by a completechange of your mind. Then you will be able to know the will of God - what isgood and is pleasing to Him and is perfect."

There is one informationfor the involution too, but not very expressively:

Matthew 23.15 - "How terrible for you, teachers of the lowand pharisees!You hypocrites! You sail the seas and cross whole countries to win one convert;and when you succed, you make him twice as deserving of going to hell asyourselves are."

Â

Based on Adam mtDNA heritage, observed only at the puberty only in"the born boy's" seminalliquid (not in vitro made - missingthe life-giving spirit because paternal mitochondria is eliminated) and , Ihave developed a new bio-communication theory, Mitochondrial Adam DNA datatransmission theory - ISBN978-606-92107-1-0, and, I hope I found the scientific explanation about thespirit (Adam mtDNA bio-magnetic field sensor) and the soul (Eve mtDNA bio-magneticfield sensor), connected in xiphoid process as Paul said in Hebrew 4.12 - "The word of God is alive and active, sharper than any double-edgedsword. It cuts all the way through, to where soul and spirit meet, to wherejoints and marrow come together."Â

I agree with the previous commenters that it is highly unlikely that we have stopped evolving. I doubt we even understand all the different factors that contribute to evolution, so how can we even assess evolution other than genetically?I also find the premise that monogamy = established paternity a bit naive, tending towards moralistic or wishful thinking rather than reality. I recall reading studies that indicate that there is more variability in genetic paternity than one might expect from outwardly monogamous relationships. I'm looking forward to the insights that genetic assessment will bring - I think lots of folks will be surprised!

Two questions not answered by the article above (though possibly in the original publication):Â how do they know that the individual reproductive fitness which they so carefully measure is genetically heritable?Â and what evidence supports the presumption that monogamy (which I take it in this context refers to a social institution) guarantees paternity?Â ;-)

Evolution in the most narrow sense is a change in population gene frequencies.Â Human populations have, do and will evolve.Â Send a group into an isolated island and you will find founder effects relatively soon.Â The headline needed a bit more thought.

Today and in the past, human selective pressures center on group cooperation via mutualized exchange between individuals (trade) which I may add is NOT group selective. This is many times more powerful a selective force than the traditional environmental pressures like the weather etc. Tribal living environmentally buffers individuals moving selective pressures to be via a fast evolving group culture. Cultural selection is not ON the group as a unit of selection but VIA the group entirely on individuals, i.e is individually selective not group selective. Confusion abounds to this day as to the critical difference.Â

Even more importantly, selection is NOT via competing totals of children simply because reproductive immatures remain sterile until they become adult. Immatureforms cannot even possibly pass on their genes. For this reason these forms can only have a zero fitness. IOW, the genes that they contain can only be selected via competition between their adult parents. Darwinian fitness is strictly and only via competing parental totals of adults reproduced per population (because only adults can possibly pass on any their genes). I term this fitness total Total Darwinian Fitness (TDF) which can alone provide a falsifiable fitness maximand for evolutionary theory. Populations evolve only because selection independently acts on adult individuals necessarily excluding the reverse as a theory falsification: individuals evolve because selection independently acts on individual genomic genes (Haldane, Hamilton and today, Dawkins' much publicized "selfish gene" centricity). If this reverse is allowed, as it is in gene centric Neo Darwinism, then evolutionary theory becomes reduced to a scientificallyÂ meaningless tautology (circular argument).

So how do you separate your "cultural selection" from sexual selection? Are you, unlike males of other apes, able to grow a beard because the tribes of your ancestors killed those who could not (that is in fact what your theory implies), or because the women preferred bearded men?Regardless, today human selective pressures are almost entirely sexual - e.g. how many children you have and how early you have your first child.

Today and in the past, human selective pressures center on group cooperation via mutualized exchange between individuals (trade) which I may add is NOT group selective. This is many times more powerful a selective force than the traditional environmental pressures like the weather etc. Tribal living environmentally buffers individuals moving selective pressures to be via a fast evolving group culture. Cultural selection is not ON the group as a unit of selection but VIA the group entirely on individuals, i.e is individually selective not group selective. Confusion abounds to this day as to the critical difference.Â

Even more importantly, selection is NOT via competing totals of children simply because reproductive immatures remain sterile until they become adult. Immatureforms cannot even possibly pass on their genes. For this reason these forms can only have a zero fitness. IOW, the genes that they contain can only be selected via competition between their adult parents. Darwinian fitness is strictly and only via competing parental totals of adults reproduced per population (because only adults can possibly pass on any their genes). I term this fitness total Total Darwinian Fitness (TDF) which can alone provide a falsifiable fitness maximand for evolutionary theory. Populations evolve only because selection independently acts on adult individuals necessarily excluding the reverse as a theory falsification: individuals evolve because selection independently acts on individual genomic genes (Haldane, Hamilton and today, Dawkins' much publicized "selfish gene" centricity). If this reverse is allowed, as it is in gene centric Neo Darwinism, then evolutionary theory becomes reduced to a scientificallyÂ meaningless tautology (circular argument).

So how do you separate your "cultural selection" from sexual selection? Are you, unlike males of other apes, able to grow a beard because the tribes of your ancestors killed those who could not (that is in fact what your theory implies), or because the women preferred bearded men?Regardless, today human selective pressures are almost entirely sexual - e.g. how many children you have and how early you have your first child.

How could Homo sapiens not evolve?Â Our evolution is a result of recombinant chromosome reproduction, alternation of generations between monoploid and diploid stages.Â This process keeps rearranging gene sets into new combinations.Â Then we have the (now measurable) ever-present mutation rate that keeps providing new genes and bits of genetic code for rearrangement or recombination to work on.Â Over time, this introduces more diversity into the gene pool of a species.Â Finally we have 'natural' selection, in all of its forms related to survival and long-term reproductive success.Â This includes sexual selection as a subset.Â Migration of genes in space follows migration of people, which is probably higher today than at any time in our past.Â This produces more combinations.Â Selection for traits that favor survival and reproduction is a necessary, continuing process.Â Without this selection, which produces continuous change, we could not maintain the useful genes that we have as they would be lost to mutation.Â The same rule applies to our species as to any other species:Â the genes that propagate more become more common, and those that propagate less become less common.Â So, if the Japanese and Italians don't reproduce successfully (and they are not at the present time), then their genes will continue to represent a smaller and smaller part of the gene population of our species.Â If you want to know what we as a species are becoming, look to where the highest reproductive rates can be found.Â Look to population demographics.Â The author of this article seems to question whether our species is still evolving.Â Think about it.Â Then try to figure out how we could not evolve.

How could Homo sapiens not evolve?Â Our evolution is a result of recombinant chromosome reproduction, alternation of generations between monoploid and diploid stages.Â This process keeps rearranging gene sets into new combinations.Â Then we have the (now measurable) ever-present mutation rate that keeps providing new genes and bits of genetic code for rearrangement or recombination to work on.Â Over time, this introduces more diversity into the gene pool of a species.Â Finally we have 'natural' selection, in all of its forms related to survival and long-term reproductive success.Â This includes sexual selection as a subset.Â Migration of genes in space follows migration of people, which is probably higher today than at any time in our past.Â This produces more combinations.Â Selection for traits that favor survival and reproduction is a necessary, continuing process.Â Without this selection, which produces continuous change, we could not maintain the useful genes that we have as they would be lost to mutation.Â The same rule applies to our species as to any other species:Â the genes that propagate more become more common, and those that propagate less become less common.Â So, if the Japanese and Italians don't reproduce successfully (and they are not at the present time), then their genes will continue to represent a smaller and smaller part of the gene population of our species.Â If you want to know what we as a species are becoming, look to where the highest reproductive rates can be found.Â Look to population demographics.Â The author of this article seems to question whether our species is still evolving.Â Think about it.Â Then try to figure out how we could not evolve.

Yes, the notion that church records would accurately record whether or not it's members were being honest when they declared their faithfulness to their respective spouses, was a detail, the veracity of which seemed highly doubtful to me as well.

Apart from that however I don't find the question of whether ourselves, or any species, may have ceased to evolve at an appreciable rate to beÂ ridiculous at all. Many species, upon finding that "perfect" niche, remain largely unchanged for millions, indeed a billion years. After all, how else can weÂ account for the existence of very ancientÂ "archeo-bacteria" and others than that theyÂ found aÂ niche whereÂ selective pressuresÂ wereÂ entirely non-existent coupled with a change so drastic when changes did occur at the niche margin (think extremophiles) none were capable ofÂ survivingÂ it. The result beingÂ a type of evolutionary statis.

While stasis is one possible option, I don't think we (yet) have the tools to adequately assess human evolution or not. And, as with any assessment, the terms need to be defined. Certainly some element of time or time period of assessment needs to be included, as well a definition of what constitutes evolution - is it a change of population frequent in so many alleles, expression of base coding (epigenetics), physical manifestation leading to a difference in ability, change in ability, ....? It may be that we can only assess evolution retrospectively over a large time span - in which case, we may not know whether we are still evolving or not.

Yes, the notion that church records would accurately record whether or not it's members were being honest when they declared their faithfulness to their respective spouses, was a detail, the veracity of which seemed highly doubtful to me as well.

Apart from that however I don't find the question of whether ourselves, or any species, may have ceased to evolve at an appreciable rate to beÂ ridiculous at all. Many species, upon finding that "perfect" niche, remain largely unchanged for millions, indeed a billion years. After all, how else can weÂ account for the existence of very ancientÂ "archeo-bacteria" and others than that theyÂ found aÂ niche whereÂ selective pressuresÂ wereÂ entirely non-existent coupled with a change so drastic when changes did occur at the niche margin (think extremophiles) none were capable ofÂ survivingÂ it. The result beingÂ a type of evolutionary statis.

While stasis is one possible option, I don't think we (yet) have the tools to adequately assess human evolution or not. And, as with any assessment, the terms need to be defined. Certainly some element of time or time period of assessment needs to be included, as well a definition of what constitutes evolution - is it a change of population frequent in so many alleles, expression of base coding (epigenetics), physical manifestation leading to a difference in ability, change in ability, ....? It may be that we can only assess evolution retrospectively over a large time span - in which case, we may not know whether we are still evolving or not.

I am sure anyone in dentistry could attest to the fact we are still evolving as there seems to be an increase of people not developing wisdom teeth within certain populations .That is probably indicative to our diet changing to predominately softer foods .

I am sure anyone in dentistry could attest to the fact we are still evolving as there seems to be an increase of people not developing wisdom teeth within certain populations .That is probably indicative to our diet changing to predominately softer foods .

Evolution is a continuous process. The extent of selectionpressure drives the rate of evolution. In case of humans, the rate of naturalselection is combated by the speed with of scientific developments have beenattained and this will continue. This means the genetic variability maintainedin human populations is high and hence more space and diversity is at disposalfor multi-dimensional evolution. Nevertheless the rate of â€˜adaptive evolutionâ€™is highly reduced.

Evolution is a continuous process. The extent of selectionpressure drives the rate of evolution. In case of humans, the rate of naturalselection is combated by the speed with of scientific developments have beenattained and this will continue. This means the genetic variability maintainedin human populations is high and hence more space and diversity is at disposalfor multi-dimensional evolution. Nevertheless the rate of â€˜adaptive evolutionâ€™is highly reduced.

Evolving within populations, of course. Are we ever likely to see another allele fixation across the whole species without a massive reduction of population? Probably not, we have a population of billions with approximately a 20 year generation time, with conditions affecting selection pressures changing on a much shorter times scale than the time to fix.Â

Evolving within populations, of course. Are we ever likely to see another allele fixation across the whole species without a massive reduction of population? Probably not, we have a population of billions with approximately a 20 year generation time, with conditions affecting selection pressures changing on a much shorter times scale than the time to fix.Â